Animation studio Pixar’s latest film, The Good Dinosaur, takes place in an alternate reality where the Cretaceous-Paleogene event that wiped out the last generation of dinosaurs never took place. While evolutionary biologists know the Cretaceous-Paleogene event did indeed rid the planet of dinosaurs, they have nurtured a hope that perhaps the wipeout was not as drastic as it seems to have been. If they are right, they believe they might have a naturalistic way to explain the mass speciation event that followed the Cretaceous-Paleogene mass extinction.
It is estimated that the Cretaceous-Paleogene event drove 75 percent or more of all species, including dinosaurs, to extinction. Geophysicists have identified two events most responsible for the widespread annihilations: (1) the Deccan supervolcanic eruptions in India and (2) the Chicxulub asteroid collision in the Yucatan Peninsula of Mexico. For decades, evolutionary biologists have speculated that these two events occurred at sufficiently different times so that many of the species populations were simply driven to very low levels, not annihilated entirely. Accordingly, the subsequent mass speciation could have included many recovery events, rather than new species appearing without any apparent ancestor.
Three recent research findings have dashed that hope. The first is that high precision argon-40/argon-39 dating has established that the Deccan supervolcanoes underwent many accelerated eruptions within 50,000 years of the asteroid collision.1 The research team responsible for this finding also demonstrated that the accelerated eruptions were “consistent with transient effects of impact-induced seismic energy.”
The second relevant discovery comes from detailed seismic modeling of the consequences of a large asteroid collision with Earth.2 This modeling shows that the ground motion from the Chicxulub impactor would have generated seismic energy densities between 0.1 and 1.0 joules per cubic meter throughout the upper 200 kilometers of Earth’s mantle. This amount of seismic energy would have been sufficient to trigger volcanic eruptions worldwide. While the geological evidence indisputably shows that the Deccan supervolcanoes were erupting before the Chicxulub impact event, the seismic modeling study demonstrates that the impact would have greatly accelerated and sustained the eruption of lava, dust, and gas from the Deccan supervolcanoes.
The third relevant finding is a tsunami deposit on the Dalmatian island of Hvar in the Adriatic Sea.3 Researchers discovered that a single tsunami laid down a deposit five meters thick. The mineral composition of the deposit contains enhanced concentrations of platinum group elements, including iridium, which are classic signatures of an asteroid collision event. In addition, fossil evidence left little doubt that the tsunami deposit was caused by the Chicxulub impact event. Such a large deposit so far away from the impact site implies that the impact event indeed was catastrophic enough to wipe out 75 percent of Earth’s species.
These recent discoveries establish that the Deccan supervolcanic eruptions peaked at the same time as the Chicxulub impact event. The combined consequences of these two events yielded a worldwide catastrophe of such enormous magnitude that no doubt remains that the Cretaceous-Paleogene mass extinction event was one of the greatest that life on Earth has ever faced.
With more than 75 percent of the preceding species completely wiped out, the mass speciation event that soon followed defies a totally naturalistic explanation. This defiance is underscored by the fact that the new species were more efficient at removing greenhouse gases from the atmosphere to compensate for the ever-brightening Sun. For example, carbon dioxide levels in the atmosphere fell from about 1,700 parts per million to about 500 parts per million.
Thousands of years before scientists discovered mass extinction events followed by mass speciation events in Earth’s geological record, the psalmist wrote about this feature of life’s history:
When you [God] hide your face, they [Earth’s creatures] are terrified. When you take away their breath, they die and return to the dust. When you send your Spirit, they are created, and you renew the face of the earth.4
Why did God so frequently replace life with new organisms? For one thing, the new life-forms were increasingly proficient at compensating for the Sun’s rising luminosity. Frequently renewing life also means that Earth is always packed with the greatest biomass, biodiversity, and biocomplexity possible within a physically changing solar system—and this means humans are thereby endowed with all the biodeposits needed to launch and sustain global high-technology civilization. Such a civilization, in turn, means that Christ’s followers can take the gospel to all the world’s people groups in a short time rather than a long time.